Digital Commons Network^™

Standardization Of E-Cigarette Research: Addressing The Analysis Of Total Nicotine And Free Base Nicotine In E-Cigarettes, Vinit Gholap

Theses and Dissertations

Electronic cigarettes (e-cigarettes) are one of the major sources of exposure to nicotine, an addictive chemical. Since 2016, the Food and Drug Administration (FDA) has started regulating these products under the Tobacco Control Act yet, specifications about the nicotine content in these products have not been established. In e-cigarettes, nicotine concentration ranges from 0 to >50mg/mL. Additionally, several e-cigarette related parameters have been identified which can affect nicotine delivery to users. Of these factors, nicotine forms (protonated and free base) have been found to play a significant role in nicotine absorption profiles yet, a limited and contradictory research is available …

Using The Memorial Sloan Kettering Frailty Index To Identify Patients At High Risk For Postoperative Intensive Care Unit Admission, Specialized Advanced Care Unit Admission, And 30-Day Readmission, Timothy J. Donoghue

Theses and Dissertations

Frailty is roughly defined as an accumulation of physiological, emotional, cognitive, and social deficits that impair a person’s response to stressful events. A frailty diagnosis has been associated with poor outcomes following surgical procedures. Cancer surgical patients aged 65 or older represent a vulnerable population susceptible to being frail and the potential associated complications that can accompany frailty. Measuring frailty is an objective risk assessment that identifies increased risk better than age or American Society of Anesthesiologists Physical Status (ASA-PS) score such that frailty can independently predict poor surgical outcomes.

Frailty is not specifically a result of having cancer, disability, …

Cardiac Arrest And Global Ischemia Reperfusion Injury: Role Of Mitochondria And Cannabinoid Receptor 2 Signaling., Jennifer L. Bradley

Theses and Dissertations

We explored the effects of cardiac arrest on mitochondria populations and heart whole tissue lysate proteomics utilizing the Weil Institute’s in vivo rat model of cardiac arrest and cardiopulmonary resuscitation. We have discovered that brain mitochondria are more sensitive to global ischemia compared to heart mitochondria. Additionally, complex I is the most sensitive electron transport chain complex to ischemic injury and is a major control point of the rate of oxidative phosphorylation following cardiac arrest and cardiopulmonary resuscitation. Preservation of brain mitochondrial activity and function during cardiac arrest may enhance outcomes and recovery.

A recent article focusing on acute myocardial …

Water Clarity At The River-Estuary Transition Zone: A Comparative Study Of The James, Mattaponi, And Pamunkey Sub-Estuaries, Rachel Henderson

Theses and Dissertations

Water clarity is a key parameter for monitoring water quality and often used to assess habitat suitability for submerged aquatic vegetation (SAV). Light attenuation, a measure of water clarity, is impacted by colored dissolved organic matter (CDOM), and by suspended particulates which include living and non-living components. We anticipated that the relative importance of these factors in regulating light attenuation would vary among the upper portions of three sub-estuaries differing in morphometry, hydrology, and degree of human influence. The James is characterized by eutrophic conditions and high algal abundance, whereas the Mattaponi and Pamunkey exhibit lower phytoplankton production. The Mattaponi …

Preventing Obesity: A Social Ecological Exploration Of Centers For Disease Control Prevention Strategies And Guidance Toward Healthy Eating, Physical Activity, And Communities, Ryan Kelly

Theses and Dissertations

Abstract

Obesity has reached nearly 40% of the adult public in the United States, costing the citizen taxpayer over $200 billion annually in healthcare costs. Those suffering from obesity deal with multiple physical and mental repercussions. Through a content analysis of four Centers for Disease Control (CDC) documents and guided by the conceptual framework of the social ecological model, this research explores the federal approach to preventing obesity. The analysis finds that CDC solutions to obesity involve connecting people to each other and healthier choices, an orientation toward local public administration, and an emphasis on environmental and infrastructure improvements. The …

Single Molecule Investigations Of Holliday Junction Binding Protein Ruva, Dalton Reed Gibbs

Theses and Dissertations

DNA breaks are inevitable as they mainly occur due to cells’ own reactive oxygen species (ROS). While DNA breaks can be single-stranded or double-stranded, the double-stranded DNA (dsDNA) breaks are more dangerous. If such damage is not repaired, it can lead to genetic instability and serious health issues including cancers. One way dsDNA breaks can be repaired is via a process called homologous recombination (HR), which involves several DNA-binding proteins. Therefore, to have a better insight into the repair mechanism and origin of repair defects, we need a better understanding of how these proteins interact with DNA itself and DNA …

Novel Roles Of Yy1 In Astrocytes, Karli A. Mockenhaupt

Theses and Dissertations

Astrocytes tile the entire central nervous system, are diverse across brain regions, and perform specialized functions fine-tuned for their neuronal circuit. Initially, astrocyte heterogeneity is generated through intrinsic programs specified by their progenitors. Then, as astrocyte mature, they are specialized by region-specific communication with surrounding cells. The molecular programs that regulate this diversity and allow for the accommodation to the needs of the local environment remains elusive. We explored a ubiquitously expressed zinc finger transcription factor, Yin Yang 1 (YY1), that both activates and represses transcription by regulating loops of active chromatin. This report describes the diverse functions of astrocytic …

Straight Through My Heart, Raul A. Aguilar Canela

Theses and Dissertations

Straight through my heart is an exhibition that explores the concept of heartbreak as a socio-political phenomenon. Through the affect of sadness the thesis analyses the way in which subjects are formed under cognitive capitalism. Paying particular interest to the collateral effects of neoliberal culture —hyper-stimulation, self-exploitation, competition, and obsession with productivity—and the pathologies they create —depression, anxiety, body aches, fatigue— this work shifts the burden of sadness from the individual to the community. By doing so it proposes heartbreak as a public feeling.

Beyond Black Or White: An Examination Of Intersectional Identities, Blame Attribution, And Sexual Violence, Ashlynn D. Bell

Theses and Dissertations

While there may be more discussions of sexual violence than there have been in previous years, cases continually arise where the responsibility of those who have been assaulted is called into question (Alaggia & Wang, 2020). Secondary victimization, or victim blaming, is partially responsible for the continued misattribution of responsibility to survivors. These perspectives minimize the experiences of survivors, which dissuades individuals from the reporting of perpetrators. The current study aimed to evaluate whether particular intersecting identities influenced perceptions of responsibility, in a hypothetical scenario depicting an assault. The race, gender identity, as well as perceptions of respectability of the …

Information Architecture For A Chemical Modeling Knowledge Graph, Adam R. Luxon

Theses and Dissertations

Machine learning models for chemical property predictions are high dimension design challenges spanning multiple disciplines. Free and open-source software libraries have streamlined the model implementation process, but the design complexity remains. In order better navigate and understand the machine learning design space, model information needs to be organized and contextualized. In this work, instances of chemical property models and their associated parameters were stored in a Neo4j property graph database. Machine learning model instances were created with permutations of dataset, learning algorithm, molecular featurization, data scaling, data splitting, hyperparameters, and hyperparameter optimization techniques. The resulting graph contains over 83,000 nodes …

Relationships Between Adverse Childhood Experiences, Inflammation And Pain In Youth And Emerging Adults With Sickle Cell Disease, Angela Pascale

Theses and Dissertations

Sickle cell disease (SCD) is a prevalent genetic disorder involving red blood cells. SCD is a multisystem disease and is connected to various severe medical complications, including debilitating pain. Though pain and inflammation have been connected to adverse childhood experiences (ACEs) in other populations, no prior work has investigated ACEs within a SCD population. The current study examined the prevalence of ACEs as well as the association of ACEs, inflammation, and pain in a sample of youth and young adults with SCD. Utilizing the biopsychosocial model of pain, I examined individual and cumulative ACEs as possible factors relating to inflammation, …

Linear And Nonlinear Optical Effects In High Carrier Concentration Oxides And Nitrides At Epsilon-Near-Zero, Ray Secondo

Theses and Dissertations

Nonlinear optics has been an important method for achieving ultrafast light manipulation. Recently, ENZ material have gained interest due to inherent advantages such as slow light, improved confinement, and ideal relaxation times, the nonlinear response of these materials, such as the intensity-dependent-refractive-index, are ultra-large yet remain ultra-fast. This experimental discovery of epsilon-near-zero enhancement has thus opened new avenues in nonlinear optics research in recent years, and while experiments have continued to progress a theoretical understanding of the processes and origins of nonlinear optical enhancement at epsilon-near-zero has lagged.

To fill this gap, the work herein focuses on uncovering the mechanisms …

Muscarinic Excitation Of Dopamine Neurons In The Ventral Tegmental Area Via Activation Of A Trpc-Like Cation Conductance, Yu Tzu Chen

Theses and Dissertations

Dopaminergic (DA) neurons in the ventral tegmental area (VTA) play a crucial role in reward and motivational behaviors, including the development of drug addictions. VTA DA neurons receive excitatory cholinergic inputs from the mesopontine tegmentum. Blockage of the M5 muscarinic receptor in DA neurons has been shown to attenuate drug-induced DA release and abuse-related behaviors, but the molecular mechanism is unknown. In this study, experiments were designed to identify the electrophysiological effects of muscarinic agonism in the modulation of action potential kinetics and firing patterns in VTA DA neurons of mice. Pharmacology of the muscarinic receptor-evoked current was also characterized. …

Comparing The Sensitivity And Specificity Of Cbct And Mri In Detecting Osteoarthritis Of The Tmj: A Systematic Review, Gabriel R. Saavedra

Theses and Dissertations

The aim of this systematic review was to compare the sensitivity and specificity of cone-beam computed tomography (CBCT) and magnetic resonance imaging (MRI) in detecting osteoarthritis (OA) of the temporomandibular joint (TMJ). This was done by using computed tomography (CT) and the research diagnostic criteria for temporomandibular disorders (RDC/TMD) as reference methods and using CBCT and MRI as index methods. A specific search strategy was developed and applied to these electronic databases: PubMed, Embase, DOSS, and Cochrane. The search results returned 802 articles, which were then narrowed down using the inclusion/exclusion criteria, to four final articles that were included in …

Racial/Ethnic Disparities In Longitudinal Trajectories Of Arrest Probability After Traumatic Brain Injury, Mickeal Pugh Jr

Theses and Dissertations

Traumatic Brain Injury (TBI) is one of the leading causes of disability across the globe, and epidemiological studies have documented a rise in this condition over the recent years. Post-TBI functional impairments can persist beyond the acute phase of the injury, and specific psychosocial and injury-related factors have predicted variability in these outcomes. Previous literature has documented profound racial/ethnic disparities in TBI risk, cause, treatment, and rehabilitation. Prior investigation has revealed an overlap between incarceration and TBI, which showed that incarcerated persons typically endorsed a history of TBI. Criminal justice literature has shown stark racial/ethnic differences in incarceration rates, which …

Fty720-Induced Antinociception In The Chronic Constrictive Injury (Cci) Mouse Model: Neuronal-Astroglial Mechanisms Through S1p1 Signaling, Lauren V. Moncayo

Theses and Dissertations

Novel pharmacological and genetic advancements increased interest in the sphingosine-1-phosphate receptor-1 (S1P₁) as a potential therapeutic target. S1P₁ plays a critical role in the mechanism of action of Fingolimod/FTY720, a therapy currently FDA-approved for the treatment of relapsing-remitting multiple sclerosis (RRMS) (Camm et al., 2014). To prevent RRMS, FTY720 downregulates S1P₁ on lymphocytes to impair their trafficking and sequester cells in the lymphoid organs to prevent further pathogenic attack (Brinkmann et al., 2010). Recent developments in pre-clinical models suggest FTY720 holds therapeutic potential to treat other diseases, such as neuropathic pain, a debilitating chronic pain …

Impact Of Targeting Glycosylated Ceramides On Tumorigenic Properties, And Characterization Of Sphingolipids In Head And Neck Tumors, Katherine E. Hylton

Theses and Dissertations

Sphingolipids play a crucial role in signaling, membrane structure, and migration, making them important molecules in cancer development, metastasis, and drug resistance. While some sphingolipids have been associated with pro-apoptotic or pro-survival behaviors, the role of many sphingolipids in cancer remains poorly defined. Chapter 1 of this study investigated the impact of three enzymes that compose most of the ceramide to Lc3 ceramide pathway – UGCG, GBA, and B3GNT5 – and how their alteration impacts chemoresistance and basal membrane invasion in vitro. It was found that the CΒE-induced inhibition of GBA, which converts glucosylceramide to ceramide, has no effects on …

Performance Study Of Respirator Filter Media And Wall Flow Filters, Peng Wang

Theses and Dissertations

The exposure of the long-term chronic particulate matter (PM) exposure and the acute increases of ambient PM has been found to aggravate the respiratory symptoms, decrease lung functions, and increase the cardiovascular morbidity and mortality. Filtration is the dominant technique used to protect both humans and environment from the pollutants including PM and gases. Among the particle filtration applications, respirators are widely applied for the protection of the public heath from the PM exposure, and wall flow filters (i.e., diesel/gasoline particulate filters) are currently employed to mitigate the PM emission from automobile engines. The above two topics are thus included …

Slowing Down The Clock: Cellular Senescence And Aging, Saad Bhatti

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

No abstract provided.

Structural Changes In Neurons In Multiple Sclerosis, Saad Bhatti

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

No abstract provided.

Exploring The Connection Between The Spontaneous Regression Seen In Neuroblastomas, Hypertumors, And Reactive Oxygen Species, Shahad Musa, Manitha Mulpuru

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

Peto’s Paradox is defined as the lack of correlation between larger animals and cancer risk. Under the assumption that all cells have equal risk of becoming cancerous, larger animals should have greater rates of cancer. However, the inverse is true. Determining the cause of this variation may allow a supplemental approach to cancer treatment. A combination of two reasons may account for this correlation including hypertumors and metabolism. Hypertumors, or cheater cells, are hypothesized to suppress cancer growth through spontaneous autophagic degradation and overexpression of the RAS g-protein. Both of these characteristics are exhibited in Neuroblastomas. An anticancer drug used …

Parametric, Nonparametric, And Semiparametric Linear Regression In Classical And Bayesian Statistical Quality Control, Chelsea L. Jones

Theses and Dissertations

Statistical process control (SPC) is used in many fields to understand and monitor desired processes, such as manufacturing, public health, and network traffic. SPC is categorized into two phases; in Phase I historical data is used to inform parameter estimates for a statistical model and Phase II implements this statistical model to monitor a live ongoing process. Within both phases, profile monitoring is a method to understand the functional relationship between response and explanatory variables by estimating and tracking its parameters. In profile monitoring, control charts are often used as graphical tools to visually observe process behaviors. We construct a …

Form Follows Culture, Nada Raafat Elkharashi

Theses and Dissertations

We all use everyday objects as part of our daily routines, but the way we use them varies from one culture to another. Using George Herbert Mead’s study of human conduct and Louis H. Sullivan’s credo, “Form follows function,” this thesis examines the cultural meanings and implications surrounding the fundamental act of drinking water. Using a methodology of iterative, exploratory making, a collection of glass vessels explores philosophical and physical manifestations of Islamic cultural principles derived from the Sunnah of Prophet Muhammad صلى الله عليه وسلم. With the goal of restoring cultural integrity to our daily activities, the work highlights …

Lonidamine Is A Novel Inhibitor Of Fatty Acid Oxidation, Tianhai He

Theses and Dissertations

In this thesis project, we examined the hypothesis that lonidamine is an effective inhibitor of FAO in mammalian cells, underling its inhibitory effects on bioenergetic production and anti-cancer action. We compared its effects on FAO and glycolysis in multiple human cancer cell lines of different lineages.

Applied Machine Learning In Extrusion-Based Bioprinting, Shuyu Tian

Theses and Dissertations

Optimization of extrusion-based bioprinting (EBB) parameters have been systematically conducted through experimentation. However, the process is time and resource-intensive and not easily translatable across different laboratories. A machine learning (ML) approach to EBB parameter optimization can accelerate this process for laboratories across the field through training using data collected from published literature. In this work, regression-based and classification-based ML models were investigated for their abilities to predict printing outcomes of cell viability and filament diameter for cell-containing alginate and gelatin composite hydrogels. Regression-based models were investigated for their ability to predict suitable extrusion pressure given desired cell viability when keeping …

Creation And Optimization Of An Optical Trapping Microfluidic Device For The Separation Of Mock Forensic Sexual Assault Samples, Mackenzie Lally

Master of Science in Forensic Science Directed Research Projects

Cell mixtures are often seen in forensic samples and commonly involve sexual assault cases where mixtures of sperm cells and vaginal epithelial cells are frequently encountered. This produces challenges in downstream analysis in the form of STR mixture profiles. The only method currently in use in crime laboratories for front-end sperm and epithelial cell separation is differential extraction. This method often results in STR mixture profiles due to carryover into both the male and female fractions and suffers from a wide range of efficiency depending on the laboratory or individual processing the sample. Optical trapping offers an alternative method for …

Biomass-Derived Electrode Materials And Sustainable Processes For Supercapacitors, Katelyn M. Shell

Theses and Dissertations

Biomass is one of the most abundant natural resources and has been used as a source of energy for thousands of years. Biomass as a precursor for energy storage materials is still relatively novel and faces several obstacles before becoming commonly used in today’s electrical devices. Currently, energy storage devices, such as batteries, capacitors, and supercapacitors, utilize petroleum-derived graphitic carbons for anodes, generating a need for more sustainable materials. Biomass, as a carbon-rich source for electrode materials, presents a viable and economically feasible alternative due to the prevalent lignocellulosic compounds: lignin, cellulose, and hemicellulose. Preliminary studies on the solid residues …

Improving Space Efficiency Of Deep Neural Networks, Aliakbar Panahi

Theses and Dissertations

Language models employ a very large number of trainable parameters. Despite being highly overparameterized, these networks often achieve good out-of-sample test performance on the original task and easily fine-tune to related tasks. Recent observations involving, for example, intrinsic dimension of the objective landscape and the lottery ticket hypothesis, indicate that often training actively involves only a small fraction of the parameter space. Thus, a question remains how large a parameter space needs to be in the first place — the evidence from recent work on model compression, parameter sharing, factorized representations, and knowledge distillation increasingly shows that models can be …

The Compass, Summer 2021

The Compass, 2018-

The Compass is an annual orientation guide for VCU students produced by the Student Media Collective in the VCU Student Media Centered. The guide is distributed physically during summer orientation sessions for new and transfer students. The publication includes short articles, illustrations, letters of welcome from students and administrators, comics, and advertisements from VCU and Richmond organizations.

“Insurance Doesn’T Care About The Patient”: An Institutional Ethnography Of The Influence Of Professional Autonomy On The Provision Care For Medicaid Dental Patients With Disabilities, Stephanie Lau

Theses and Dissertations

In terms of unmet needs for people with disabilities (PWD), dental care is number three behind residential care and employment (Fisher, 2012). Regardless of disability, oral healthcare traverses all disability diagnoses and can be a significant factor in quality of life (Deckler, 2011; Griffin et al., 2007; Norwood & Slayton, 2013). When attempting to secure oral healthcare, people with disabilities face many challenges, including lack of access, lack of provider education on proper care of PWD, and difficulty finding a willing dental provider (Deckler, 2011; Fisher, 2012; Kennedy, 2009).

The purpose of this study was to investigate professional practices and …